Since bills passed by the House and Senate may contain varying language and provisions, conference committees are joint committees that resolve differences between bills. After a perfected bill is created, the conference committee returns it to the House and Senate for a final vote.
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The Northwest Passage is a famed sea route from the Atlantic Ocean to the Pacific Ocean through a group of sparsely populated Canadian islands known as the Arctic Archipelago. Climate change has caused Arctic ice cover to thin in recent years, opening the passage to marine shipping.